Make-Ahead Chocolate French Toast

Spray a 13x9 inch baking pan with nonstick cooking spray. Cut the French bread into 6 slices, each 1 ½ inches thick. Using a small, sharp knife, cut 2-inch-long slits in one side of each bread slice, cutting ¾ of the way thru the bread, to create a pocket.
Spoon 2 heaping tbs of chips into the pocket of each bread slice. Press to close. Place filled slices into prepared baking pan. Whisk together eggs, milk, cinnamon, and vanilla in medium bowl. Pour egg mixture evenly over bread. Carefully turn pieces over, spooning mixture in pan over top of bread. Cover pan with plastic wrap. Refrigerate several hours, or overnight.
Heat oven to 400º. Bake, uncovered, 20 to 25 minutes or until golden brown.